Electro-optic (EO) modulators, which convert signals from the electrical to optical domain plays a key role in modern optical communication systems. Lithium niobate on insulator (LNOI) technology has emerged as a competitive solution to realize high-performance integrated EO modulators. In this Letter, we design and experimentally demonstrate a Mach–Zehnder interferometer-based modulator on a silicon nitride loaded LNOI platform, which not only takes full advantage of the excellent EO effect of ${\rm{LiNb}}{{\rm{O}}_3}$, but also avoids the direct etching of ${\rm{LiNb}}{{\rm{O}}_3}$ thin film. The measured half-wave voltage length product of the fabricated modulator is 2.24 V·cm, and the extinction ratio is ${\sim}{{20}}\;{\rm{dB}}$. Moreover, the 3 dB EO bandwidth is ${\sim}{{30}}\;{\rm{GHz}}$, while the modulated data rate for on–off key signals can reach up to 80 Gbps.

中文翻译：

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绝缘体平台上基于氮化硅负载铌酸锂的高速电光调制器

将信号从电域转换为光域的电光 (EO) 调制器在现代光通信系统中起着关键作用。绝缘体上铌酸锂 (LNOI) 技术已成为实现高性能集成 EO 调制器的有竞争力的解决方案。在这封信中，我们在氮化硅负载的 LNOI 平台上设计并实验证明了基于 Mach-Zehnder 干涉仪的调制器，它不仅充分利用了${\rm{LiNb}}{{\rm{ O}}_3}$，同时也避免了${\rm{LiNb}}{{\rm{O}}_3}$薄膜的直接蚀刻。测得的调制器半波电压长度积为2.24 V·cm，消光比为${\sim}{{20}}\;{\rm{dB}}$. 此外，3 dB EO 带宽为${\sim}{{30}}\;{\rm{GHz}}$，而开关键信号的调制数据速率可以达到 80 Gbps。